【作者】 陈涛；

【导师】 郭院成；

【作者基本信息】 郑州大学 ， 结构工程， 2010， 博士

【摘要】 随着国民经济的发展和西部大开发战略的实施以及当前为扩大内需而进行的大规模基础设施投资项目的建设,近年来在西部地区,航空运输业取得了长足进展,一大批机场相继建成或改扩建。与中东部相比,西部山区地带的机场建设共同面临一系列特殊的工程问题,如高填方、高海拔、高地震烈度、高边坡、地质条件复杂、气候条件差、建设周期短、工程质量要求高等问题。西部山区机场高填方填料多为由岩石爆破而来的大粒径块碎石,其中以巨粒土最为常见。从已有的工程实践来看,当前在山区修筑高填方机场主要面临着三个亟待解决的现实问题：1、巨粒土填料的填筑压实质量控制问题。2、高填方填筑体的沉降变形问题。3、高填方填筑体(边坡)的稳定性尤其是地震条件下的稳定性问题。本文针对西部山区机场高填方工程建设中遇到的上述典型问题进行了研究,主要内容如下：1.我国现行民航机场道面设计规范对道面土基的强度、变形均未提出明确的技术要求,各个机场在地基处理时对道槽区土基时采用的控制标准也不尽相同,给实际应用带来一定的困难。针对目前广泛应用的机场水泥混凝土道面,运用美国联邦航空局道面设计程序,对比分析了土基强度等设计参数对混凝土道面板厚度的影响规律；通过有限元数值模拟方法,分析了土基不均匀沉降对道面结构性能的影响,根据道面结构功能性和结构性要求确定了机场土基不均匀沉降参考值。2.巨粒土越来越广泛的应用于山区高填方工程实践中,但对压实标准及压实质量的检测与评价等方面还有很多问题模糊不清,无法满足工程应用要求。对巨粒土压实的影响因素及巨粒土填筑压实质量控制指标进行了分析；对巨粒土的压实标准、干密度与强度及变形指标的关系进行了研究,提出采用“视压实度”来评价填料的相对压实程度。介绍了康定机场巨粒土填料强夯处理工程及昆明新机场巨粒土填料碾压及冲压处理工程两个工程实例,提出了现场施工时一些实用的压实质量控制方法。3.在高填方地基的沉降中,填筑体的沉降要占较大比例。对于填筑体的自身压缩变形计算,目前还没有通行的方法。以康定机场B段高填方填筑体为例,对土面区进行了施工监测,采用龚帕斯生长曲线模型对高填方地基沉降进行了预测,并与对数模型、双曲线模型进行了对比,发现用龚帕斯生长曲线模型预测效果较好。4.变形与稳定是山区高填方机场、公路、铁路路堤修筑中首先遇到而且必须研究解决的两大问题。基于强度折减有限元方法,分平坦地基与斜坡地基两种情况,就山区路堤的基本特点,主要分析原始地貌、原地基条件、填筑速度、填筑体压实度、地下水出露位置、设置支挡、反压护道等因素对山区高路堤变形和稳定性的影响。5.地震荷载作用下边坡的动力响应及稳定性研究是当前岩土工程研究的一个的热点和难点问题。采用有限元程序进行地震时程动力分析,分析了地震荷载作用下坡高、坡比、地震波参数(包括振幅、频率和持续时间)、软夹层等因素对高填方地基边坡的位移、加速度等动力响应的影响规律；基于边坡动力响应特征,分析边坡的变形破坏机理,提出地震荷载作用下边坡动力安全系数的确定方法；在上述研究成果的基础上,对九寨-黄龙机场元山子沟段高填方边坡进行了地震稳定性分析,同时通过不同方法进行了对比。更多还原

【Abstract】 With the development of national economy,the implementing of Development of West Regions and the construction of large-scale basic establishment for expanding domestic demand nowadays, the airport construction in the mountainous southwest of China is coming into a prosperous period,where a great deal of airports have been built or renovated. Compared with the middle and east regions, the airport construction in mountainous southwest, face a series of special engineering problems, such as high embankment, high altitude, intensive earthquake, high slope, complex geological conditions accompanied with soft soil, bad climate condition, short construction period and strict project quality requirements are the main characteristics for these airports.The fillings of high-fill projects in the mountainous southwest of China come from the blasting of large particle size block detritus usually, and over coarse-grained soils are the most common fillings. From the engineering practice in the past time, the building of mountainous high-fill airport mainly faces three urgent problems in the current:1.The control problem of compaction quality with over coarse-grained soils.2.The settlement calculation problem of over coarse-grained soils filling.3. The stability of high-fill slope, especially the stability under the conditions of the earthquake. Based on the typical problem encountered in the high-fill airport construction in western mountainous, the main contents are studied as follows:1. The current civilian airfield design code for the strength and deformation of soil foundation is not clear, it bring some practical difficulties for engineering application. To determine the appropriate criteria of subgrade strength and deformation for airport concrete pavement, the effects of four parameters, including subgrade strength, base course thickness, base course modulus and concrete flexural strength, on concrete slab thickness were analyzed and compared based on pavement design procedure. Through the finite element numerical simulation method and theoretical analysis, the influence of subgrade deformation on pavement structural and functional performances was also studied.2. Nowadays over coarse-grained soils are widely applied in high-fill engineering practices in mountains areas, but such problems as compacting standards、quality inspection and evaluation are not clear to these days, so they can not satisfy actual application requirements. In this paper compaction effect factors and compaction quality control indexs for over coarse-grained soils are analyzed; Compaction standards and the connection of dry density with intensity and deformation standard indexs are studied as well; a new method (visual compaction) to evaluate the relative compaction degree of filling is putting forward. In this section two engineering examples are introduced, one is the compaction treatment engineering of the over coarse-grained soils filling in Kangding airport, the other is the compaction and stamping processing project in Kunming airport, at last some practical compaction quality control methods are put forward.3. A large proportion is occupied by the settlement of filling embankment in the settlement of high-fill foundation. For its own compression settlement of filling embankment,There is no general deformation calculation method. Take section B of Kangding airport high-fill filling embankment for example, the construction of soil surface areas are measured, and Gompertz living curve model is used to forecast the high-fill foundation settlement. Compared with Logarithm model and Hyperbolic model, we can find out that the effect of settlement forecasting of Gompertz living curve model is best.4. Deformation and stability of the embankment are two major problems in the construction of mountainous high-fill airports, highways, railways. Based on the finite element method with strength reduction technique, according to two basic characteristics--flat foundation and slope foundation, the deformation and stability of mountainous high-fill embankment are analyzed considering such influencing factors as original foundation, landscape, the filling speed, filling compaction degree, groundwater, sustaining structure, loading berm etc.5. Under seismic load of the slope dynamic response and stability is the current hot and difficult problem of geotechnical engineering. Using finite element software for earthquake time-history analysis, analyzed displacement and acceleration under the different seismic load, slope height, slope ratio, seismic waves factors (including amplitudes, frequencies, duration time), soft soil layer and so on. Based on the analysis of the slope dynamic response characteristics, destruction mechanism under seismic load and the slope dynamic method to determine the safety factor are put forward. In the research, Yuan shan zi channel of Jiuzhai-Huanglong airport high-fill slope stability under earthquake is analyzed, and compared different methods meanwhile.更多还原